Keep the work brief specific
Explain the people needing facilities, existing bathrooms and what parts of the property stay occupied. Ask about standard cabins, washing and accessible options as relevant. The simplest useful arrangement is one that meets the actual need without obstructing everyday movement.
Preserve the later approach
Materials, parked vehicles or a new gate can change access after delivery. Explain those stages and review service visits with the property contact. Confirm any repositioning, extension and collection rather than assuming the supplier can use a different route without discussion.